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Abstract—Local management of solar photovoltaic and battery inverters is seen as a means to mitigate many grid issues that can result from large penetrations of distributed and variable solar energy. This work demonstrates through simulation how local inverter operation can fit within an operational paradigm referred to as packetized energy management. In particular, the power factor at which energy packets are injected in to the grid from a distributed set of energy resources (i.e., batteries) are adjusted in discrete steps over the range of operation. Unlike approaches where a device’s power factor is adapted continuously over time, the discrete-time and asynchronous nature of the investigated approach avoids potential system oscillations. We present simulation results for a feeder line consisting of 100 battery systems comparing our distributed, locally-controlled approach to one centrally determined and controlled. 

A hybrid control architecture for nonlinear dynamical systems is described which combines the advantages of model based control with those of real-time learning. The idea is to generate input-output data from an error system involving the plant and a proposed model. A discretized Chen-Fliess functional series is then identified from this data and used in conjunction with the model for predictive control. This method builds on the authors’ previous work on model-free control of a single-input, single-output Lotka-Volterra system.The problem is revisited here, but now with the introduction of a model for the dynamics. The single-input, multiple-output version of the problem is also investigated as a way to enhance closed-loop performance 

Context. The Southern Photometric Local Universe Survey (S-PLUS) is a project to map ~9300 sq deg of the sky using twelve bands (seven narrow and five broadbands). Observations are performed with the T80-South telescope, a robotic telescope located at the Cerro Tololo Observatory in Chile. The survey footprint consists of several large contiguous areas, including fields at high and low galactic latitudes, and towards the Magellanic Clouds. S-PLUS uses fixed exposure times to reach point source depths of about 21 mag in the 𝑔riɀ and 20 mag in theuand the narrow filters. Aims. This paper describes the S-PLUS Data Release 4 (DR4), which includes calibrated images and derived catalogues for over 3000 sq deg, covering the aforementioned area. The catalogues provide multi-band photometry performed with the toolsDoPHOTandSExtractor– point spread function (PSF) and aperture photometry, respectively. In addition to the characterization, we also present the scientific potential of the data. Methods. We use statistical tools to present and compare the photometry obtained through different methods. Overall we find good agreement between the different methods, with a slight systematic offset of 0.05 mag between ourPSFand aperture photometry. We show that the astrometry accuracy is equivalent to that obtained in previous S-PLUS data releases, even in very crowded fields where photometric extraction is challenging. The depths of main survey (MS) photometry for a minimum signal-to-noise ratioS/N= 3 reach from ~19.5 for the bluer bands to ~21.5 mag on the red. The range of magnitudes over which accuratePSFphotometry is obtained is shallower, reaching ~19 to ~20.5 mag depending on the filter. Based on these photometric data, we provide star-galaxy-quasar classification and photometric redshift for millions of objects. Results. We demonstrate the versatility of the data by presenting the results of a project to identify members of four Abell galaxy clusters in the Local Universe. The S-PLUS DR4 data allow for a reliable assessment of cluster membership out to a large radius corresponding to 5 ×r₂₀₀. The S-PLUS DR4 can be accessed through the survey data portal. All the software used to generate the catalogues for this release and the scientific investigation presented is available in the collaboration GitHub repository. Conclusions. The S-PLUS DR4 consists of a large, calibrated public dataset, providing powerful ways for studying Galactic and extra-galactic objects through an extensive set of (broad and narrow) filters.